Method of producing ammonium perchlorate.



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{Tooll wh'ooi it may concern:

UNITED salaries PATENT OFFICE.

OSCAR BIBG'EB Gammon, or mlmsno, nvns'rn, SWEDEN, ASSIGNOR 'ro OSCAR sacrum CARLSON, F STOCKHOLM, SWEDEN.

reunion or PRODUCING Amvromtnir rnncnnona'rn.

Specification 0! Letters Patent.

Application filed January 13, 1910. Serial No. 537,762.

Patented Feb. 28,1911.

lie it. lcnown that I, QBCAR"BIRGER Cam.-

son', a subject of the King of Swcdel'l, and.

resident of Mnsbo, A'vest a, in the Kingdom of Sweden, have inventedrertain new and useful Improvements in the Method of Producing Ammonium Perchlorate, of which the following is a specification.

In practice it has been found impossible to produc ammonium porchlora'te directly from ammonium chlorid by clccl'zrolysis on account of the instability of the intermedimouium salt. in'the market, and the. present ingwcdium perchlorate ntc product, viz. the ununonium chlorate. Cno has, therefore, lieen leftto the conv cn nion, by moons of ammonium chlorid, of sodium perchlorate, which can be produced by electrolysis. A method of converting so-.

dunn perchlorate by means of ammonium nitrate has also been patented, but this method is, from a technical cndfeconomical point of view, inferior to the first mentioned one. a

. Experience has, however, proved that it is possible in prnctlce to use for the said purpose ammonium sulfate, the cheapest aminvcntion has for its object a method of-prd dueingan'nnqnium perchlorate by convertby moans of ammonium sulfate. k

If one tries'to separate ammonium perchloratcby means of crystallisation irom thcvlye obtained by addingammunium' sul-- Fate to'sodiuin perchlorate after the said live has'been sufficiently concentrated in any d'e-- sired manner, ammonium perchlorate will settle on cooling the-said lyc. out at a certain point the byproduct, viz. sodium sulfate, will also crystallize, oantaining molecules-of water of crystallization. On

' account of this a fresh quantity of ammoni'um perchlorate inclosed Wlthin the sodium sulfate will also be deposited. It is therefore very difiicult and expensive to separate 4E ammonium.perchlorate "from the by-prodnot 'in this way. This fact- .whichis based upon the known condition oforystallization ofsodium sulfate, is evidently the reason why ammonium Sulfate has not hitherto ammonium perchlorate. Further investigations have .proved, that the greatest part of the ammonium perchlorate has, contrary to expectat-ion, crystallized before the crystallization of the sodium sulfate takes place, and morephenomena of supersaturation, at

perchlorate, which is still in the mother liqnor, the latter is concentrated by boiling, whereby waterfrec sodium sulfate deposits while the liquor is hot and is separated before the same has become cold. In this manner a fresh portion of ammonium perchlorate is obtained, and so on. The ammo nium perchlorate obtained in this way conto ins but a small quantity of sodium sulfate, as the solubility of the ,waterfrec so dium sulfate increases when temperature decreases. In the above manner the amnc onium perchlorate can be. quantitatively u'tilizcd'at the same time as the sodium sulfate is obtained free from water and am- 11nonia. evaporation, the mother liquors may be einployed to dissolve fresh quantities of so If one should not wish to use dium perchlorate and ammonium sulfate. In these operatlons waterfree' sodium sulfate also deposits from the solutions and is then removed.

It has been found that, on account of the f conditions of solubility, it is possible to pro coed in two ways in practically making the conversion. According to the first way hot solutions of ammonium sulfate and sodium perchlorate are mixcdtogcthw-oue of these solutions may also be replaced by the corresponding salt in solid stute-=whcreupon the ammonium perchlorate deposits, when the solution is cooled. According to the secmid way cold solutions are used; one of these may also be replaced bysolid salt. In this -the. temperature will rise from 35-40 because heat is developed in the conversion; 'l .he greatestjamt of tho salt. dcposlts during the mlxmg operatiolu Temperature 1s then allowed to fall to about. +22,-and ammo nium perchlorateds"separated from the mother. liqucrrbefore the sodium sulfate with 10 molecules of water of crystalliza tion begins to crystallize.

The above mentioned method of 'produe iilg ammonium perchlorate alsoofi'crs other l liquid by a 'lutions may beused in th case the cisterns are Stance be employed.

, which evidently depends on advantages tlmn.'tl10se,' which are due tethe lower rice of ammonium sulfate.

In the foregoing it is stated, that cold 50- e conversion, whereby steam is ecouomizecl and; furthermore, the cost of installation will be very low as no crystallization cisterns are neerled for the raw salt, which deposits directly (luring the mixing operation. Furthern'mrc, the use of metallic vessels is obj ectionable when mmnon'ium chloricl 01' ammonium nitrute are used as raw materials, as in this acted upon by the liqlf, on the coutrz'uy, he used, ciste l'ns'of land may for; in-

The lead is in this case evidel ltly protected against the act-ion oil. the covering of lead sulfa tew W'hen u1 mn o uiuu1 chlcricl or ammonium nitrate is usech. nitrous gases are easily' evolved, an intermediate insulation of nitrogeu-chlorid (N01,). This is no! only dangerous for the health oft-he men, hut also causes :1 loss of valuable mnmmiin-nitrogen; This inconvenience is n-oiclerl when anuncnium sulfate is wsecl,

uizl, fate ammonium sul Sodium nitrate and sodium chlorid will be less soluble at lower. tom Je'reture, while sodium sulfate as stated aliove becomes more easily soluble. When-usiu a OItlOn of the by-prouct deposits toget er with the ammonium perchloiate.

monium sulfate-and crystallizing out the a'mm'onium perchlorate while the temperature is not lower than 22 0., substantially as described. i In witness whereof, I-'lmve hereunto signed my name in thc presence of two subscribing witnesses. .OSGAB B-IRGER GARLSON.

Vlitnesses AXEL Ennuc'uu,

OSCAR, GRA-L-IN.

the old methods 

